This invention relates to an adjustment mechanism with a unique drive assembly configuration for adjusting the position of a vehicle seat. Specifically, the drive assembly includes a drive nut that is rotated with respect to a bracket during assembly to form a positive structural engagement between the bracket and the drive nut.
Seat adjusters are often used in seat assemblies for selectively adjusting the position of a vehicle seat. Typically a first track member is fixed to a vehicle structure, such as a floor, and a second track member is supported with respect to the first track member for movement relative to the first track member such that the seat position can be adjusted horizontally in forward or rearward directions with respect to the vehicle. The adjustment of the seat assembly is performed by either a mechanical actuator, an electrical actuator, or an electromechanical actuator.
Typically, non-mechanical horizontal seat adjustment is accomplished by using an electric motor and a driving mechanism. The driving mechanism is usually either a gear assembly or a spindle and nut assembly. As the gear or spindle and nut assemblies are driven by the motor, the second track moves relative to the first track until the seat is in the desired position.
These known driving mechanisms are complex and have a significant number of components that require a great deal of packaging space. The significant number of components also makes assembly of the seat adjuster difficult and time consuming because each of the components has to be installed into the adjuster with fasteners and other mounting hardware. This also significantly increases the cost of the seat adjuster.
Thus, it is desirable to have a seat adjuster with a drive assembly that is easy to assemble and reduces the overall number of required components. It is also desirable to have a seat adjuster with a drive assembly that provides sufficient strength with fewer components, fasteners and mounting hardware so that assembly cost and overall assembly weight is reduced, and available packaging space for other vehicle components is increased.